1. Field of the Invention
The present invention relates to a method for diagnosing Alzheimer's disease and, particularly, to a method for diagnosing Alzheimer's disease at an early stage.
2. Description of the Related Art
Dementia is a brain injury that has a seriously malignant influence on personal activity. Among the most common forms of senile dementia is Alzheimer's disease, which is a neurodegenerative disease involving problems with the executive functions of thinking, memory and language.
Much is known about the cause of Alzheimer's, but not comprehensively. No therapeutics that can cure the disease have been discovered thus far. Administration with drugs such as tacrine (Cognex), donepezil (Aricept), rivastigmin (Exelon), or galanthamine (Razadyne, also conventionally known as Reminyl) only temporarily mitigates the progression of Alzheimer's disease in patients in the early or moderate stages.
Alzheimer's disease is characterized by cognitive impairment and is caused by the deposition of beta-amyloid plaques and the formation of neurofibrillary tangles (NFTs) inside nerve cell bodies of brain cell.
Many therapies exist and are developed trying to treat Alzheimer's disease through various approaches. In contrast, relatively fewer studies have been done with regard to simple methods for the early diagnosis of Alzheimer's disease.
For example, Korean Patent Application Publication No. 2009-0048192 discloses a method for the diagnosis of Alzheimer's disease in which the expression level of Fcγ-receptor IIb is measured.
Conceived from the finding that Fcγ-receptor IIb is directly involved in the signal transduction of beta-amyloid, this invention pertains to the diagnosis, prevention and treatment of Alzheimer's disease and a screening method of Alzheimer's disease, characterized by determining the expression level of Fcγ receptor IIb.
In the patent publication, the expression level of Fcγ-receptor IIb can be determined by using a fluorescence detection method in which a fluorescent or color compound is conjugated to a compound binding specifically to Fcγ-receptor IIb and is quantitatively measured.
Also in this patent publication, when an antibody specific to Fcγ-receptor IIb is used, the antibody is allowed to react with a secondary antibody conjugated to a fluorescent substance, is washed, and is analyzed by using a fluorescence microscope or scanner. When a compound specific to Fcγ-receptor IIb is used, the bound compound may be quantified in a bound or separated state.
Korean Patent No. 10-0903526 describes a biosensor using a field effect transistor for detecting a specific biomolecule.
As disclosed in this patent, the FET-type biosensor that can detect the presence of or determine the concentration of a specific biomolecule on the basis of the principle of a field effect transistor (FET) is fabricated by forming a self-assembled monolayer on a passivation layer deposited over a metal thin layer, thus taking advantage of all conditions available for CMOS integrated circuit processes.
Korean Patent Application Publication No. 10-2009-0110101 discloses a method for patterning nerve cells using magnetic nanoparticles, in which an external magnetic field is applied to magnetic nanoparticle-containing nerve cells to induce the extension of neurites.
This method has an advantage over conventional methods, in that it needs not use specific chemicals and cell scaffolds and can be applied to various kinds of cells irrespective of cell types or tissue properties.
In recent years, the early diagnosis of Alzheimer's disease has been implemented by determining the expression level of beta-amyloid, presumed to be the greatest cause of Alzheimer's disease, under a microscope or by analyzing its gene, in association with a fluorescent material.
Being based on optical or chemical techniques, however, conventional diagnosis methods of Alzheimer's disease suffer from the disadvantage of being difficult to perform in real time and requiring high costs for diagnosis. Further, related diagnosis kits of Alzheimer's disease are difficult to produce on a mass scale.